A number of radiographic imaging methods are currently used to visualize radiopaque structures in the human body. These imaging methods are used to help diagnose disease and to guide therapeutic procedures. Exemplary radiographic imaging methods include radiographs, fluoroscopy, and computed tomography (CT).
When using these imaging methods to create images of internal structures, anatomical features that are visible on the patient and on the image can be used as points of reference for determining proper location for needle insertion through the skin or for other surgical or therapeutic procedures. In these cases, a metallic or other radiopaque instrument, such as, for example, a hemostat, paperclip or needle, and a skin marking device, usually in the form of a skin marking pen, are used to locate and mark a specific location on the skin surface. Since the radiopaque instrument will be visible in the image, the instrument is placed over a patient's body and repositioned during imaging until the radiopaque instrument overlies the desired radiopaque point of reference in the human body, usually a bony structure when using fluoroscopy, and then the marking device is used to mark the location on the patient's skin. This marking procedure typically requires two hands and exposes the individual performing the procedure, such as, for example, a physician or technician, to increased radiation because one or both of their hands are near the imaging field for a prolonged period. Once the procedure is completed, the radiopaque instrument and the marking device are typically disposed of. Occasionally, the radiopaque instrument is resterilized at a significant cost and reused. Simply reusing the same radiopaque instrument and pen on multiple patients introduces the risk of infection being spread between patients and many hospitals have instituted policies prohibiting this.